This invention relates generally to the field of heat dissipation equipment for use in work machines such as construction, earthmoving and other types of machines and, more particularly, to a pair of fans positioned in a vertically stacked arrangement for cooling a plurality of heat transfer devices positioned therearound.
Construction and excavation type work machines as well as a wide variety of other types of work machines are used commonly for a wide variety of various construction and development purposes. Heat is a natural by-product of the engine and the other functional equipment associated with work machines and must therefore be dissipated efficiently in order to keep the engine and other equipment within proper operating temperature limits for optimum and continued sustained performance. As a result, a wide variety of different types of cooling systems are utilized to accomplish this task.
There is also a continuous need to improve emissions and the efficiency of work machines, which needs may be achieved in part by improving the overall performance and efficiency of the cooling systems and other heat dissipation equipment associated with a particular work machine. Typically, a fan is installed in series with a plurality of heat exchanger cores. Such prior art fan configurations typically impede optimal heat dissipation and optimal positioning of the heat exchanger cores and adversely affect the efficiency and balance of the overall machine. Such prior art designs also add to the overall size of the machine which must be kept to a minimum due to space limitations as well as dimensional constraints on operator visibility. In this regard, the packaging length of the cooling system is typically limited by the axial spacing of the power train components, and the width of such system is typically limited by the existing frame rail dimensions, and the desire for operator visibility puts limitations on cooling systems and therefore hood height. Such serial positioning of the heat exchanger cores also makes it difficult to clean out debris carried by the air flow and blown into the fins of the various serially positioned heat exchanger cores. Debris collected in the fins insulates the transfer of heat therefrom thereby adversely impacting the performance and efficiency of the heat dissipation equipment and the overall machine.
Utilizing a single fan to provide cooling to a plurality of heat exchanger cores also requires use of a larger diameter fan to accomplish the necessary cooling. This may translate into a larger axial length since fan depth increases with fan size. This arrangement likewise adds to the overall size of the cooling system and the machine.
Future challenges in designing machine cooling systems also extend to reducing the overall noise associated with working machines. In this regard, it is necessary to attenuate engine and equipment related noise emitted by work machines in order to meet stricter noise regulations globally. Fans installed serially or axially usually add to the overall size of the system thereby affording more opportunity for the sound waves emitted therefrom to propagate to the exterior of the machine thereby contributing to noise pollution.
It is therefore desirable to provide a fan arrangement which will dissipate heat more efficiently from a plurality of heat exchanger cores in a work machine; to provide a well balanced construction wherein the cooling system package is reduced in overall size; to package a plurality of heat exchanger cores about the fan arrangement; to reduce the occurrence of debris entering the cooling system package; and to attenuate noise emitted by the fans in all directions.
Accordingly, the present invention is directed to overcoming one or more of the problems as set forth above.
In one aspect of this invention, a cooling system for cooling heat transfer devices in a work machine is disclosed. The cooling system includes a plurality of fans positioned so as to be located in the same plane, a first heat transfer device positioned upstream from the plurality of fans, a second heat transfer device positioned downstream and adjacent one side of the fans, a third heat transfer device positioned downstream and adjacent the opposite side of the fans, and the fans creating air flow through the first, second and third heat transfer devices.
In another aspect of this invention, a method for cooling heat transfer devices in a work machine is disclosed. The method includes the steps of positioning a plurality of fans so as to be located in the same plane, positioning a first heat transfer device upstream from the plurality of fans, positioning a second heat transfer device downstream and adjacent to one side of the fans, positioning a third heat transfer device downstream and adjacent to the opposite side of the fans, and creating air flow through the first, second and third heat transfer devices by the fans.